<template>
  <view>
    <view class="search-box">
      <my-seach @click="gotoSearch"></my-seach>
    </view>
    <!-- 分类 -->
    <view class="scroll-view-conainer">
      <!-- 左侧滑动区域 -->
      <scroll-view scroll-y="true" :style="{height: wh+'px'}" class="left-scroll-view">
        <block v-for="(item,i) in cateList" :key="i">
          <view :class="['left-scroll-view-item' , active === i ?'active':''] " @click="activeChanged(i)">{{item.cat_name }}</view>
        </block>
      </scroll-view>
      <!-- 右侧滑动区域 -->
      <scroll-view scroll-y="true" :style="{height: wh + 'px'}" class="right-scroll-view " :scroll-top="scrolltop">
        <view class="cate-lv2" v-for="(item2 ,i2) in cateLevel2" :key="i2">
          <!-- 二级分类标题 -->
          <view class="cate-lv2-title">/{{item2.cat_name}}/</view>
          <!-- 三级分类 -->
          <view class="cate-lv3-list">
            <view class="cate-lv3-item" v-for="(item3 , i3) in item2.children" :key="i3" @click="gotoGoodsList(item3)">
              <image :src="item3.cat_icon"></image>
              <text>{{item3.cat_name}}</text>
            </view>
          </view>
        </view>
      </scroll-view>
    </view>
    
  </view>
</template>

<script>
  import badgeMix from '@/mixins/tabbar-badge.js' // 导入自己封装的 mixin 模块
  export default {
    mixins:[badgeMix],
    data() {
      return {
        wh:0 ,//屏幕的可用高度
        cateList:[] ,//分类列表数据
        active:0 ,// 当前选中项的索引，默认让第一项被选中
        cateLevel2: [] ,// 二级分类列表
        scrolltop:0
      };
    },
    onLoad(){
       // 获取当前系统的信息
      const sysInfo = uni.getSystemInfoSync()
      // console.log(sysInfo)
       // 为 wh 窗口可用高度动态赋值
      this.wh=sysInfo.windowHeight - 50
      
      this.getCateList()
    },
    methods: {
      async getCateList() {
        const {data:res}=await uni.$http.get('/api/public/v1/categories')
        if(res.meta.status !==200) return uni.$showMsg()
        this.cateList=res.message
        this.cateLevel2=res.message[0].children
      },
      activeChanged(i){
        this.active=i
        this.cateLevel2=this.cateList[i].children 
        this.scrolltop=this.scrolltop=== 0 ? 1:0
      },
      gotoGoodsList(item3){ //商品点击跳转
        uni.navigateTo({
          url:'/subkg/goods_list/goods_list?cid='+ item3.cat_id
        })
      },
      gotoSearch(){
        uni.navigateTo({
          url:'/subkg/search/search',
        })
      }
    },
  }
</script>

<style lang="scss">
.scroll-view-conainer{
  display: flex;
  .left-scroll-view{
    width: 120px;
    .left-scroll-view-item{
      line-height: 60px;
      background-color: #f7f7f7;
      text-align: center;
      font-size: 12px;
      &.active{ // 激活项的样式
        background-color: #ffffff;
        position: relative;
        
        &::before{ // 渲染激活项左侧的红色指示边线
              content: '';
              display: block;
              width: 3px;
              height: 30px;
              background-color: #c00000;
              position: absolute;
              left: 0;
              top: 50%;
              transform: translateY(-50%);
              }
      }
      
    }
  }
  
  .right-scroll-view{
    .search-box{
      position: sticky;
      top: 0px;
    }
    
    .cate-lv2-title{
      font-size: 12px;
      text-align: center;
      font-weight: bold;
      padding: 15px 0;
    }
    .cate-lv3-list{
      display: flex;
      flex-wrap: wrap;
      .cate-lv3-item{
        width: 33.33%;
        display: flex;
        flex-direction: column;
        justify-content: center;
        align-items: center;
        margin-bottom:10px ;
        image{
          width: 60px;
          height: 60px;
        }
        text{
          font-size: 12px;
        }
        
      }
    }
    
    
  }
  
}
</style>
